Magnetic multi-needle biopsy capsule robot and control method thereof

Abstract

The invention provides a magnetic multi-needle biopsy capsule robot and a control method thereof. The capsule robot comprises a capsule shell, end penetrating holes are formed in the two ends of the capsule shell, a side penetrating hole is formed in one side of the middle of the capsule shell, and the interior of the capsule shell is divided into a left chamber, a middle chamber and a right chamber; a first biopsy needle and a second biopsy needle are arranged in the middle chamber; the first permanent magnet is configured to drive the first biopsy needle to extend out of the side through hole under the driving of an external magnetic field; the resetting mechanism is configured to drive the first biopsy needle to reset; a second biopsy needle is arranged in each of the left chamber and the right chamber; the second permanent magnet is configured to drive the second biopsy needle to rotationally extend out of the adjacent end penetrating hole under the driving of an external rotating magnetic field; the spiral structure is configured to enable the second permanent magnet to move along the axis when the second permanent magnet rotates around the central axis of the spiral structure. According to the invention, the needle can be withdrawn from a plurality of parts in a single examination to obtain tissue samples, so that the comprehensiveness of biopsy and the accuracy of diagnosis are improved.

Description

Technical Field

[0001] The present application relates to the technical field of medical devices, and particularly to a magnetic multi-needle biopsy capsule robot and a control method thereof. Background Art

[0002] Capsule endoscopy (CE) is an advanced gastrointestinal disease diagnosis technology that has emerged in recent decades. However, in terms of robot movement, they require active mobility and versatility to achieve extensive, unconstrained, and precise clinical applications. The main drawback of existing CE is that it only has the function of image acquisition. However, doctors hope that CE can undertake more clinical tasks, such as biopsy or drug delivery. The biopsy function is an important research direction because it can effectively help doctors judge the patient's condition. In recent years, research has been dedicated to integrating biopsy tools into CE, such as blades, grippers, forceps, and fine needles. Using a blade to cut the target lesion or using forceps to tear the target tissue may cause wounds or discomfort.

[0003] In contrast, fine needle biopsy is a minimally invasive biopsy technique that has been widely used in biopsies of human organs such as the kidney, liver, thyroid, and breast. In recent years, this technique has been successfully introduced into the design of the CE biopsy module. To drive the biopsy tool, an actuator may be required. Commonly used actuators include springs, motors, and permanent magnets (PMs). However, the disadvantage of using a spring actuator is that it can only be triggered once, and using a motor as an actuator has problems of space and energy consumption. Therefore, PM is a relatively ideal driving method. The permanent magnet actuator is usually used in conjunction with an electromagnetic actuation (EMA) system, and the driving force can be remotely provided by the EMA system. Therefore, using a PM actuator does not consume the energy of the built-in battery. In addition, its space occupancy is smaller than that of a motor, which is very important for reducing the volume of CE.

[0004] Currently, there are some magnetic drive biopsy capsule (MABC) robots for gastrointestinal diagnosis in the prior art. The robot realizes movement and biopsy functions under the control of an external electromagnetic drive (EMA) system, and can achieve two types of active movements, one is planar movement, and the other is three-dimensional movement; planar movement means that the robot rolls on the surface of the gastrointestinal tract with a rotating uniform magnetic field; three-dimensional movement means that the robot moves in three-dimensional space under the control of the EMA system. After reaching the target position, the biopsy needle can be ejected for sampling and then retracted under the gradient magnetic field.

[0005] However, although these traditional endoscopes can effectively observe the digestive tract, they are often limited by factors such as sampling location, quantity, and tissue diversity during biopsy. Although the proposed mechanism can facilitate endoscopic examination and biopsy procedures, it has limitations in clinical applications. Due to space constraints, it is impossible to perform multiple biopsies in different target areas. However, the proposed mechanism can be used for multi-tissue biopsy at the same target point or along a section of the intestine in suspicious or abnormal situations, such as in elderly patients who may have difficulty undergoing conventional endoscopy due to discomfort and side effects. Also, the proposed capsule can easily function in tubular organs (small intestine and large intestine), but it can only take one sample and can only perform single-needle biopsy. Summary of the Invention

[0006] In order to improve the problems that the existing technology is often limited by factors such as sampling location, quantity, and tissue diversity during biopsy, and it is difficult to perform multiple biopsies in different target areas due to space constraints, the present application provides a magnetic multi-needle biopsy capsule robot and its control method.

[0007] In the first aspect, a magnetic multi-needle biopsy capsule robot provided by the present application adopts the following technical solutions: A magnetic multi-needle biopsy capsule robot includes a capsule housing. Both ends of the capsule housing are provided with end perforations, and one side of the middle part of the capsule housing is provided with a side perforation. The interior of the capsule housing is divided into a left chamber, a middle chamber, and a right chamber; The following are arranged in the middle chamber: A first biopsy needle, which is arranged corresponding to the side perforation; A first permanent magnet, the first biopsy needle is fixed on the first permanent magnet, and the first permanent magnet is configured to drive the first biopsy needle to extend out of the side perforation under the drive of an external magnetic field; and A reset mechanism, which is configured to drive the first biopsy needle to reset; The following are arranged in both the left chamber and the right chamber: A second biopsy needle, which is arranged corresponding to the adjacent end perforation; A second permanent magnet, the second biopsy needle is coaxially fixed to the end of the second permanent magnet, and the second permanent magnet is configured to drive the second biopsy needle to rotate and extend out of the adjacent end perforation under the drive of an external rotating magnetic field; and A spiral structure, which is configured to enable the second permanent magnet to move along its axis when the second permanent magnet rotates around its axis.

[0008] Furthermore, the two magnetic poles of the first permanent magnet are arranged at both axial ends thereof, and the two magnetic poles of the second permanent magnet are arranged on both sides of its axis; in the initial state, the magnetic pole polarities of the same side of the first permanent magnet and the second permanent magnet are the same.

[0009] Furthermore, the reset mechanism includes: Two slide rails are provided and are arranged on both sides of the first permanent magnet, and the slide rails are arranged along the radial direction of the capsule housing; A slider is slidably sleeved on the slide rail, and the first permanent magnet is fixedly connected between the two sliders; A reset spring is sleeved on the slide rail and is located between the first permanent magnet and the side perforation.

[0010] Furthermore, the spiral structure includes: A spiral block is wrapped around the outer periphery of the second permanent magnet; A spiral groove is provided on the inner peripheral wall of the capsule housing and is threadedly adapted to the spiral block, and the spiral groove is provided in both the left chamber and the right chamber.

[0011] Furthermore, baffles are fixedly connected in the inner cavities of the left chamber and the right chamber close to the adjacent end perforations, the baffles are located on the side of the spiral groove away from the first permanent magnet, and through holes for the second biopsy needle to pass through are formed through the baffles.

[0012] Furthermore, the spiral directions of the spiral grooves in the left chamber and the right chamber are the same.

[0013] Furthermore, both the first biopsy needle and the second biopsy needle have an inclined tip, and barbs are provided in the inner cavity of the inclined tip, and the barbs extend in a direction close to the middle of the capsule housing.

[0014] Furthermore, two partition plates are fixedly connected in the capsule housing, and the two partition plates divide the capsule housing into the left chamber, the middle chamber and the right chamber.

[0015] In a second aspect, a control method for a magnetic multi-needle biopsy capsule robot provided by the present application, based on the above-mentioned magnetic multi-needle biopsy capsule robot, includes the following steps: S1. The patient swallows the capsule housing, and the capsule housing is attracted by an external magnetic field control to move the capsule housing to the lesion; S2. Based on the same magnetic pole polarities of the first permanent magnet and the two second permanent magnets on the same side, the capsule housing is fixed by a first external magnetic field; S3. When the first biopsy needle needs to take a sample, the first permanent magnet is repelled or attracted by a second external magnetic field, so that the first permanent magnet drives the first biopsy needle to extend out of the side perforation, wherein the magnetic field strength of the second external magnetic field is greater than the magnetic field strength of the first external magnetic field; S4. When the second biopsy needle is required for sampling, an external rotating magnetic field is used to drive the corresponding second permanent magnet to rotate in the capsule housing. With the aid of the spiral structure, the second permanent magnet drives the second biopsy needle thereon to extend out from the corresponding end perforation, wherein the magnetic field intensity of the external rotating magnetic field is not less than that of the first external magnetic field.

[0016] Furthermore, when controlling the second biopsy needle in the left chamber for sampling, first move the first external magnetic field to correspond to the middle chamber and the right chamber, and then control the second permanent magnet in the left chamber with the external rotating magnetic field; the same applies when controlling the second biopsy needle in the right chamber for sampling.

[0017] In summary, the present application includes at least one of the following beneficial technical effects: 1. By outputting the first external magnetic field with the external electromagnetic drive system (EMA system), the first permanent magnet and the two second permanent magnets with the same polarity on the same side can be synchronously adsorbed, so as to fix the capsule housing more stably, effectively avoiding phenomena such as displacement, deflection, and flipping of the capsule housing during the needle-out process, and ensuring the precise alignment of the first biopsy needle and the two second biopsy needles; 2. When the first biopsy needle needs to extend for sampling, the first permanent magnet can be adsorbed or repelled by the second external magnetic field, so that the first permanent magnet drives the first biopsy needle to move radially along the capsule housing and extend out from the side perforation for sampling; when the second biopsy needle needs to extend for sampling, for example, taking the second biopsy needle in the left chamber for sampling as an example, an external rotating magnetic field can be applied to the second permanent magnet in the left chamber. At this time, the second permanent magnet drives the second biopsy needle to rotate and extend out of the end perforation for sampling under the action of the external rotating magnetic field; since the magnetic field intensities of both the second external magnetic field and the external rotating magnetic field are less than that of the first external magnetic field, therefore, neither the first biopsy needle nor the second biopsy needle will affect the stability of the capsule housing when the needles are out. 3. The capsule robot of the present application can obtain tissue samples from multiple sites during a single examination by integrating multiple biopsy needles in the capsule housing, improving the coverage and tissue diversity of the biopsy, thereby improving the comprehensiveness of the biopsy and the accuracy of the diagnosis. Especially in complex or diseased areas, more tissue information can be obtained; and magnetic drive multi-needle biopsy is adopted, which can be remotely controlled without an internal power supply, realizing precise sampling in multiple directions, laying a foundation for the precise sampling technology of digestive tract diseases in the clinical process. 4. The miniaturized design of the capsule shell can freely pass through the complex bends or narrow parts of the digestive tract, providing a wider range of biopsy opportunities. At the same time, this application adopts an external electromagnetic drive (EMA) system to control the telescopic and movement of the biopsy needle, which means that the robot does not require internal battery power supply; through the action of an external magnetic field, the movement of the corresponding permanent magnet and the biopsy needle can be accurately controlled, avoiding the problem of battery consumption, increasing the durability and reliability of the device; moreover, this battery-free design also reduces the potential risks of the internal battery of the device, avoiding problems such as battery aging or leakage, and further improving the safety of the system. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the present invention or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are some embodiments of the present invention. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0019] Figure 1 is the overall structural schematic diagram of the embodiment of this application; Figure 2 is the partial cross-sectional structural schematic diagram of the embodiment of this application; Figure 3 is the schematic diagram of the magnetic field distribution when the first biopsy needle samples in the embodiment of this application; Figure 4 is the schematic diagram of the magnetic field distribution when the second biopsy needle samples in the embodiment of this application; Figure 5 is the cross-sectional view mainly used to show the bevel tip and barbs in the embodiment of this application; Figure 6 is the demonstration diagram when the capsule robot in the embodiment of this application samples different lesion tissues; (a) controlling the capsule robot to approach the target tissue with the first external magnetic field; (b) controlling the second biopsy needle to protrude for sampling with an external rotating magnetic field; (c) the second biopsy needle finishes sampling; (d) controlling the first biopsy needle to protrude for sampling with the second external magnetic field; (e) the first biopsy needle finishes sampling; (f) after the second biopsy needle protrudes under the control of the external rotating magnetic field, controlling the capsule robot to approach the target tissue with the first external magnetic field and making the second biopsy needle penetrate for sampling; (g) the second biopsy needle finishes sampling; Figure 7 is the force analysis diagram when the first biopsy needle samples in the embodiment of this application; (a) is the relationship diagram between the distance between the second external magnet and the capsule robot and the force Fm on the first permanent magnet; (b) is the relationship diagram between the moving displacement of the first permanent magnet and the force Fz exerted by the second permanent magnet on the first permanent magnet; (c) is the relationship diagram between the compressed stroke of the return spring and the elastic force Fk; (d) is the relationship diagram between the moving displacement of the first permanent magnet and the sum of the forces Fk, Fz, and Fn; Figure 8 It is the force analysis diagram when the second biopsy needle of the embodiment of the present application takes a sample; (a) is the relationship diagram between the distance between the third external magnet and the capsule robot and the gravitational force received by the capsule robot; (b) is the relationship diagram between the distance between the third external magnet and the capsule robot and the magnetic torque of the second permanent magnet. Figure 9 It is the relationship diagram between the distance between the first external magnet and the capsule robot of the embodiment of the present application and the forces on the capsule robot and the first permanent magnet.

[0020] Reference numerals: 1. Capsule housing; 11. End perforation; 12. Side perforation; 13. Partition board 21. Left chamber; 22. Middle chamber; 23. Right chamber 31. First biopsy needle; 32. Second biopsy needle; 331. Oblique tip; 332. Barbs 41. First permanent magnet; 42. Second permanent magnet 51. Slide rail; 52. Slide block; 53. Return spring; 54. Mounting seat 61. Spiral block; 62. Spiral groove; 63. Baffle; 631. Through hole Detailed implementation manners

[0021] To make the objectives, technical solutions and advantages of the present invention clearer, the technical solutions in the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the present invention. Apparently, the described embodiments are some but not all of the embodiments of the present invention. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present invention without creative efforts shall fall within the protection scope of the present invention.

[0022] Refer to Figure 1 and Figure 2 , an embodiment of the present application discloses a magnetic multi-needle biopsy capsule robot, which includes a capsule housing 1. End perforations 11 are provided at both ends of the capsule housing 1, and a side perforation 12 is provided on one side of the middle of the capsule housing 1. The interior of the capsule housing 1 is partitioned into a left chamber 21, a middle chamber 22, and a right chamber 23. Specifically, two partition boards 13 are fixedly connected inside the capsule housing 1, and the two partition boards 13 partition the capsule housing 1 into a left chamber 21, a middle chamber 22, and a right chamber 23.

[0023] The following are provided in the middle chamber 22: A first biopsy needle 31, which is arranged radially along the capsule housing 1 and corresponds to the side perforation 12; A first permanent magnet 41, the first biopsy needle 31 is fixed on the first permanent magnet 41, and the first permanent magnet 41 is configured to drive the first biopsy needle 31 to extend out of the side perforation 12 under the drive of an external magnetic field; and A reset mechanism, configured to drive the first biopsy needle 31 to extend out of the side perforation 12 and then reset automatically.

[0024] Both the left chamber 21 and the right chamber 23 are provided with: A second biopsy needle 32, arranged along the axis of the capsule housing 1 and corresponding to the adjacent end perforation 11; A second permanent magnet 42, the second biopsy needle 32 is coaxially fixed to the end of the second permanent magnet 42, and the second permanent magnet 42 is configured to drive the second biopsy needle 32 to rotate and extend out of the adjacent end perforation 11 under the drive of an external rotating magnetic field; and A spiral structure, configured to enable the second permanent magnet 42 to move along its axis when the second permanent magnet 42 rotates around its central axis.

[0025] Moreover, in specific configuration, the two magnetic poles of the first permanent magnet 41 are arranged at both axial ends thereof, the two magnetic poles of the second permanent magnet 42 are arranged on both sides of its central axis, the first permanent magnet 41 is specifically an annular magnet, and the second permanent magnet 42 is specifically a radial magnet; in the initial state, the magnetic pole polarities of the same side of the first permanent magnet 41 and the second permanent magnet 42 are the same. For this reason, the second permanent magnet 42 in the shape of a cylinder is further arranged eccentrically with respect to the capsule housing 1 while keeping the axes parallel, so as to reduce the influence of the external rotating magnetic field controlling the rotation of the first permanent magnet 41 on the attitude of the capsule housing 1.

[0026] Thus, when using the capsule robot of the present application, after the patient swallows the capsule housing 1, an external magnetic field is output by means of an external electromagnetic drive system (EMA system), defined as a first external magnetic field, to synchronously adsorb the first permanent magnet 41 and the two second permanent magnets 42, and move the capsule housing 1 to the lesion site of the patient. Since the magnetic pole polarities of the same side of the first permanent magnet 41 and the two second permanent magnets 42 are the same in the initial state, the three can be strongly adsorbed by means of the strong magnetic field of the first external magnetic field, so as to stably fix the capsule housing 1, and effectively avoid phenomena such as displacement, deflection, and flipping of the capsule housing 1 that may occur during the needle insertion process, and can ensure the precise alignment of the first biopsy needle 31 and the two second biopsy needles 32.

[0027] When the first biopsy needle 31 needs to extend for sampling, the first permanent magnet 41 can be attracted or repelled by the second external magnetic field, so that the first permanent magnet 41 drives the first biopsy needle 31 to move radially along the capsule housing 1 and extend from the side perforation 12 for sampling. By setting the magnetic field intensity of the second external magnetic field to be greater than that of the first external magnetic field, when the first biopsy needle 31 exits the needle, it will not affect the stability of the capsule housing 1, and the accuracy of needle exit can be ensured. After the first biopsy needle 31 finishes sampling, the second external magnetic field is removed, and the first biopsy needle 31 retracts into the capsule housing 1 under the action of the reset mechanism, and the next step can be carried out. For the schematic diagram of the magnetic field action, please refer to specifically Figure 3 .

[0028] When the second biopsy needle 32 needs to extend for sampling, for example, taking the second biopsy needle 32 in the left chamber 21 for sampling, an external rotating magnetic field can be applied to the second permanent magnet 42 in the left chamber 21. Specifically, an external magnet rotates around the axis of the capsule housing 1, and with the attraction of the external magnet to the second permanent magnet 42, the second permanent magnet 42 follows the external magnet to rotate in the capsule housing 1. At this time, the second permanent magnet 42 has a tendency to rotate in the left chamber 21 under the action of the external rotating magnetic field. By setting the magnetic field intensity of the external rotating magnetic field to be not less than that of the first external magnetic field, at this time, the capsule housing 1 will not move or rotate relative to the external electromagnetic drive system. Therefore, the second permanent magnet 42 can rotate independently in the capsule housing 1. For the schematic diagram of the magnetic field action, please refer to specifically Figure 4 . With the setting of the spiral structure, when the second permanent magnet 42 rotates in the left chamber 21, it will also drive the second biopsy needle 32 to move axially along the capsule housing 1. Therefore, by controlling the rotation direction of the external rotating magnetic field, the second biopsy needle 32 can be controlled to extend out of the corresponding end perforation 11 of the left chamber 21 for sampling. After sampling, the second permanent magnet 42 is controlled to rotate reversely in the left chamber 21 through the external rotating magnetic field, so that the second biopsy needle 32 retracts into the capsule housing 1, and the next step can be carried out.

[0029] Among them, during specific control, the first biopsy needle 31 and the two second biopsy needles 32 can be controlled to exit the needle in sequence, or simultaneously, or after controlling one first biopsy needle 31 and one second biopsy needle 32 to exit the needle, then controlling the other second biopsy needle 32 to exit the needle. The needle exit method can be flexibly adjusted according to the actual inspection requirements.

[0030] Therefore, the capsule robot of the present application integrates multiple biopsy needles within the capsule housing 1, enabling the acquisition of tissue samples from multiple sites during a single examination, improving the coverage and tissue diversity of biopsies, thereby enhancing the comprehensiveness of biopsies and the accuracy of diagnosis. In particular, more tissue information can be obtained in complex or diseased areas. Moreover, magnetic drive multi-needle biopsies are employed, allowing for remote control without an internal power source, achieving precise sampling in multiple directions, and laying the foundation for precise sampling techniques for digestive tract diseases during clinical procedures.

[0031] Furthermore, the miniaturized design of the capsule housing 1 enables it to freely pass through complex bends or narrow parts of the digestive tract, providing a wider range of biopsy opportunities. At the same time, the present application uses an external electromagnetic drive (EMA) system to control the telescoping and movement of the biopsy needles, which means that the robot does not require internal battery power. Through the action of an external magnetic field, the movement of the corresponding permanent magnet and biopsy needle can be precisely controlled, avoiding the problem of battery consumption, increasing the durability and reliability of the device. Moreover, this battery-free design also reduces the potential risks of internal batteries in the device, avoiding problems such as battery aging or leakage, and further improving the safety of the system.

[0032] Specifically, referring to Figure 1 and Figure 2 , the above-mentioned reset mechanism includes: Sliding rails 51, two of which are provided and arranged on both sides of the first permanent magnet 41. The sliding rails 51 are arranged along the radial direction of the capsule housing 1; Sliders 52, slidably sleeved on the sliding rails 51. The first permanent magnet 41 is fixedly connected between the two sliders 52. Specifically, a mounting seat 54 is fixedly connected between the two sliders 52, the first permanent magnet 41 is fixedly connected to the mounting seat 54, and the first biopsy needle 31 also passes through the hollow part of the first permanent magnet 41 and is fixedly connected to the mounting seat 54; Reset springs 53, sleeved on the sliding rails 51 and located between the first permanent magnet 41 and the side perforation 12.

[0033] In this way, when a second external magnetic field is applied to the first permanent magnet 41, the first permanent magnet 41 can be moved in the direction close to the side perforation 12, causing the sliders 52 to slide on the sliding rails 51 in the direction close to the side perforation 12. At this time, the reset springs 53 are compressed and deformed. When the second external magnetic field is removed after sampling, the elastic deformation forces of the two reset springs 53 drive the two sliders 52 to slide in the direction away from the side perforation 12, and then the second permanent magnet 42 drives the first biopsy needle 31 to retract into the interior of the capsule housing 1, enabling the automatic needle retraction action of the first biopsy needle 31.

[0034] Referring to Figure 1 and Figure 2 , the above-mentioned spiral structure includes: The spiral block 61 is wrapped around the outer periphery of the second permanent magnet 42. The spiral block 61 is specifically cylindrical and has spiral protrusions on the outside. The second permanent magnet 42 is coaxially fixed in the inner cylinder of the spiral block 61. The second biopsy needle 32 fixed to one end of the second permanent magnet 42 penetrates through the end of the spiral block 61. Specifically, the second biopsy needle 32 is fixed to the end of the spiral block 61.

[0035] The spiral groove 62 is provided on the inner peripheral wall of the capsule housing 1 and is threadedly adapted to the spiral block 61. The left chamber 21 and the right chamber are both provided with the spiral groove 62. And the spiral directions of the spiral grooves 62 in the left chamber 21 and the right chamber are the same, so that the rotation directions of the external rotating magnetic fields required by the second permanent magnets 42 in the left chamber 21 and the right chamber in the needle-out state are opposite, so that the needle-out and needle-in of the two second biopsy needles 32 will not interfere with each other.

[0036] Moreover, baffles 63 are also fixed in the inner cavities of the left chamber 21 and the right chamber close to the adjacent end perforations 11. The baffles 63 are located on the side of the spiral groove 62 away from the first permanent magnet 41. Through holes 631 for the second biopsy needle 32 to pass through are formed through the baffles 63.

[0037] In this way, when an external rotating magnetic field is applied to the second permanent magnet 42, the second permanent magnet 42 drives the spiral block 61 to rotate in the spiral groove 62 of the capsule housing 1 under the drive of the external rotating magnetic field, and the rotational lateral movement of the second permanent magnet 42 in the capsule housing 1 can be realized, so as to realize the rotational needle-out and needle-in of the second biopsy needle 32. The baffle 63 is used to limit the minimum distance for the spiral block 61 to drive the second biopsy needle 32 to approach the end perforation 11, so as to prevent the second biopsy needle 32 from being inserted excessively during sampling or the spiral block 61 from coming out of the spiral groove 62.

[0038] Furthermore, this battery-free spiral mechanism is controlled by an external magnetic field and does not require battery drive, reducing the complexity and maintenance cost of the device. By precisely adjusting the external rotating magnetic field, precise control of the second biopsy needle 32 can be achieved, enabling it to be positioned and collect biopsy samples in the gastrointestinal tract.

[0039] In addition, referring to Figure 1 and Figure 5 , in order to prevent the samples after sampling from falling off the needle heads of the first biopsy needle 31 or the second biopsy needle 32, both the first biopsy needle 31 and the second biopsy needle 32 have beveled tips 331, and barbs 332 are provided in the inner cavities of the beveled tips 331, and the barbs 332 extend in the direction close to the middle of the capsule housing 1.

[0040] In this way, after the first biopsy needle 31 and the second biopsy needle 32 are inserted to obtain samples, the tissue sample enters the syringe of the first biopsy needle 31 or the second biopsy needle 32 through the bevel tip 331. The barbs 332 in the inner cavity of the bevel tip 331 can achieve the effect of hooking the tissue entering the syringe, which can effectively prevent the sampled sample from slipping out of the syringe during the movement of the capsule housing 1 after sampling is completed, ensuring the sampling quality of the capsule robot of the present application.

[0041] The embodiment of the present application also discloses a control method for a magnetic multi-needle biopsy capsule robot. Based on the above-mentioned magnetic multi-needle biopsy capsule robot, the following technical solutions are adopted: A control method for a magnetic multi-needle biopsy capsule robot, referring to Figure 1 and Figure 2 , includes the following steps: S1. The patient swallows the capsule housing 1, and the capsule housing 1 is attracted by an external magnetic field control to move the capsule housing 1 to the lesion.

[0042] S2. Based on the same pole polarities of the first permanent magnet 41 and the two second permanent magnets 42 being the same, the capsule housing 1 is fixed by the first external magnetic field.

[0043] S3. When the first biopsy needle 31 needs to sample, the first permanent magnet 41 is repelled or attracted by the second external magnetic field, so that the first permanent magnet 41 drives the first biopsy needle 31 to protrude from the side perforation 12 and penetrate into the lesion tissue for sampling, as shown in Figure 6 in (d) and Figure 6 in (e); where the magnetic field intensity of the second external magnetic field is greater than the magnetic field intensity of the first external magnetic field; after the first permanent magnet 41 completes sampling, the elastic deformation forces of the two return springs 53 can achieve the automatic retraction of the first biopsy needle 31.

[0044] S4. When the second biopsy needle 32 needs to sample, the corresponding second permanent magnet 42 is driven to rotate in the capsule housing 1 by an external rotating magnetic field. With the aid of the spiral structure setting, the second permanent magnet 42 drives the second biopsy needle 32 thereon to protrude from the corresponding end perforation 11 and penetrate into the lesion tissue for sampling, as shown in Figure 6 in (a), Figure 6 in (b) and Figure 6 in (c); where the magnetic field intensity of the external rotating magnetic field is not less than the magnetic field intensity of the first external magnetic field.

[0045] Among them, when sampling with the second biopsy needle 32 in the left chamber 21, first move the first external magnetic field to correspond to the middle chamber 22 and the right chamber, and then control the second permanent magnet 42 in the left chamber 21 with the external rotating magnetic field; similarly, when sampling with the second biopsy needle 32 in the right chamber, first move the first external magnetic field to correspond to the middle chamber 22 and the left chamber 21, and then drive the external rotating magnetic field to control the second permanent magnet 42 in the right chamber. Thus, by separating the first external magnetic field with a larger magnetic field intensity from the working external rotating magnetic field, the mutual interference between the two magnetic fields can be reduced to a certain extent, while ensuring the fixing effect of the first external magnetic field on the capsule robot during the needle extraction process; moreover, the influence of the first external magnetic field on the second permanent magnet 42 during operation can also be reduced to a certain extent, ensuring that the external rotating magnetic field can stably and effectively drive the target second permanent magnet 42 to drive the second biopsy needle 32 to rotate and extract the needle.

[0046] Moreover, considering the diversity of the lesion site and tissue size, during the actual sampling process, the second biopsy needle 32 can first be rotated and extracted by the external rotating magnetic field, and then the capsule housing 1 can be driven by the first external magnetic field to insert the second biopsy needle 32 after needle extraction into the lesion tissue for sampling, as Figure 6 shown in (f) of Figure 6 and (g) of

[0047] In a specific example, as Figure 3 and Figure 4 shown, a first external magnet (labeled B1) is set to generate a first external magnetic field, a second external magnet (labeled B2) is set to generate a second external magnetic field, and a third external magnet (labeled B3) rotates around the capsule housing 1 to generate an external rotating magnetic field, where the area of the second external magnet is smaller than that of the first external magnet, but its magnetic field intensity is greater than that of the first external magnet.

[0048] When the first biopsy needle 31 needs to extract the needle for sampling, by moving the second external magnet closer to the capsule housing 1, the first permanent magnet 41 drives the first biopsy needle 31 to move 5 mm and penetrate into the diseased tissue. Among them, when the first permanent magnet 41 descends 2.5 mm, the magnetic pole dividing line of the first permanent magnet 41 and the magnetic pole dividing lines of the two second permanent magnets 42 are on the same horizontal line; therefore, during the 5 mm travel of the first permanent magnet 41, there are two force application stages.

[0049] The first stage: During the process of the first permanent magnet 41 moving 2.5 mm, the forces acting on it are the reaction force of the return spring 53 (Fk), the magnetic force of the two second permanent magnets 42 on the first permanent magnet 41 (Fz), the resistance of piercing the tissue (Fn), and the magnetic force applied by the second external magnet to the first permanent magnet 41 (Fm). The magnetic force applied by the second external magnet to the first permanent magnet 41 is calculated as follows: Fm > 2Fk + Fz + Fn.

[0050] The second stage: During the process of the first permanent magnet 41 moving from 2.5 mm to 5 mm, the forces acting on it are the reaction force of the return spring 53 (Fk), the magnetic force of the two second permanent magnets 42 on the first permanent magnet 41 (Fz), the resistance of piercing the tissue (Fn), and the magnetic force applied by the second external magnet to the first permanent magnet 41 (Fm). The magnetic force applied by the second external magnet to the first permanent magnet 41 is calculated as follows: Fm + Fz > 2Fk + Fn.

[0051] When the first biopsy needle 31 pierces the tissue, the second external magnet is removed. The first permanent magnet 41 moves towards the first external magnet under the action of the compressive deformation force of the return spring 53, and the first biopsy needle 31 retracts into the capsule housing 1. During this process, the first permanent magnet 41 also has two force-bearing stages during its movement.

[0052] The first stage: During the process of the first permanent magnet 41 moving back 2.5 mm, the forces acting on it are the elastic force of the return spring 53 (Fk), the magnetic force of the two second permanent magnets 42 on the first permanent magnet 41 (Fz), and the resistance of withdrawing from the tissue (Fn). At this time: 2Fk > Fz + Fn.

[0053] The second stage: During the process of the first permanent magnet 41 moving back from 2.5 mm to 5 mm, the forces acting on it are the elastic force of the return spring 53 (Fk), the magnetic suction force of the two second permanent magnets 42 on the first permanent magnet 41 (Fz), and the resistance of withdrawing from the tissue (Fn). At this time: 2Fk + Fz > Fn.

[0054] Furthermore, through further force analysis, as shown in Figure 7 (a) in it, it shows the magnitude of the force Fm acting on the first permanent magnet 41 when the distance between the second external magnet and the capsule housing 1 changes; as shown in Figure 7 (b) in it, it shows the magnitude of the force Fz exerted by the two second permanent magnets 42 on the first permanent magnet 41 as the first permanent magnet 41 moves (a positive value indicates that the force direction is away from the side perforation 12, and a negative value indicates that the force direction is towards the side perforation 12). As shown in Figure 7 (c) in it, it shows the magnitude of the elastic force Fk of a single return spring 53. As shown in Figure 7In (d), the sum of the forces Fk, Fz, and Fn is shown, with a maximum of 3.54 N. Therefore, the magnetic force exerted by the second external magnet on the first permanent magnet 41 should be greater than 3.54 N. That is, when the second external magnet is within 11 mm of the capsule robot, it can ensure that the first biopsy needle 31 successfully extends and penetrates the tissue. When the second external magnet is removed, the first permanent magnet 41 is only affected by Fk, Fz, and Fn. As can be seen from Figure 7 (d), the sum of these three forces is greater than 0 during the movement of the first permanent magnet 41. That is, the direction of the force on the first permanent magnet 41 always tends to retract the first biopsy needle 31. Therefore, when the second external magnet is removed, the first biopsy needle 31 can retract into the capsule housing 1 under the action of the return spring 53.

[0055] When the second biopsy needle 32 needs to be extended for sampling, taking the second biopsy needle 32 on the right side of the capsule housing 1 as an example, when the third external magnet is controlled to approach the right end of the capsule housing 1 and rotate clockwise around the axis of the capsule housing 1, a rotating magnetic field will be generated. Under the action of this magnetic field, the second biopsy needle 32 on the second permanent magnet 42 will rotate out. Then, a thrust is applied to the capsule robot by the first external magnet to make the extended second biopsy needle 32 penetrate the tissue. Then, the capsule robot is pushed again by the first external magnet to make the second biopsy needle 32 leave the tissue to ensure the integrity of the tissue sample and avoid unnecessary damage to the surrounding tissue.

[0056] Finally, the third external magnet is controlled to approach the right end of the capsule housing 1 and rotate counterclockwise. At this time, the change in the magnetic field will cause the second biopsy needle 32 to retract into the capsule housing 1. Figure 8 In (a), the forces on the capsule robot when the distance between the third external magnet and the capsule housing 1 changes are shown. The gravitational force of the third external magnet on the capsule robot should be less than the gravity of the capsule robot; otherwise, the capsule robot will be adsorbed above the intestinal wall. The gravity G of the capsule robot is about 0.072 N. Therefore, the minimum distance of the third external magnet from the capsule housing 1 is 8 cm.

[0057] Figure 8 In (b), the magnetic torque acting on the second permanent magnet 42 is shown. Through experimental measurement, the minimum magnetic torque that can drive the second permanent magnet 42 and the spiral block 61 to rotate is 0.218 mN·m. When the third external magnet is 15 cm away from the capsule robot, the magnetic torque is 0.21 mN·m, which is less than the minimum magnetic torque for the rotation of the second permanent magnet 42. Therefore, the maximum distance of the third external magnet from the capsule housing 1 is controlled at 14 cm to ensure the smooth extension of the second biopsy needle 32. Finally, it can be concluded that when the distance between the third external magnet and the capsule housing 1 is in the range of 8 cm to 14 cm, the needle can be successfully extended.

[0058] And after the second biopsy needle 32 extends, the capsule robot is then driven by the first external magnet to make the second biopsy needle 32 penetrate the tissue.Figure 9 It shows the forces on the capsule robot and the force on the first permanent magnet 41 when the distance between the first external magnet and the capsule housing 1 changes. It can be seen that after the second biopsy needle 32 exits the needle, when the first external magnet pushes the capsule housing 1 to move, the force on the first permanent magnet 41 is very small. The weight of the capsule robot is 0.072 N, and the force for the second biopsy needle 32 to penetrate the tissue is 0.42 N. Therefore, the force of the first external magnet on the capsule robot should be greater than 0.482 N. That is to say, when the first external magnet is more than 20 mm away from the capsule robot, it can drive the capsule robot to move and penetrate the tissue without causing the first permanent magnet 41 to move downward.

[0059] The implementation principle of a magnetic multi-needle biopsy capsule robot according to an embodiment of the present application is as follows: By means of an external electromagnetic drive system (EMA system) to output a first external magnetic field, the first permanent magnet 41 and two second permanent magnets 42 with the same polarity on the same side can be synchronously adsorbed, so as to stably fix the capsule housing 1, effectively avoiding phenomena such as displacement, deflection, and flipping of the capsule housing 1 during the needle-exiting process, and ensuring the precise alignment of the first biopsy needle 31 and the two second biopsy needles 32.

[0060] When the first biopsy needle 31 needs to extend for sampling, the first permanent magnet 41 can be adsorbed or repelled by a second external magnetic field, so that the first permanent magnet 41 drives the first biopsy needle 31 to move radially along the capsule housing 1 and extend from the side perforation 12 for sampling; when the second biopsy needle 32 needs to extend for sampling, for example, taking the second biopsy needle 32 in the left chamber 21 for sampling as an example, an external rotating magnetic field can be applied to the second permanent magnet 42 in the left chamber 21. At this time, the second permanent magnet 42 drives the second biopsy needle 32 to rotate and extend from the end perforation 11 for sampling; since the magnetic field intensities of both the second external magnetic field and the external rotating magnetic field are less than the magnetic field intensity of the first external magnetic field, therefore, whether the first biopsy needle 31 exits the needle or the second biopsy needle 32 exits the needle, it will not affect the stability of the capsule housing 1.

[0061] Moreover, the capsule robot of the present application integrates multiple biopsy needles in the capsule housing 1, can obtain tissue samples from multiple sites during a single examination, improves the coverage and tissue diversity of the biopsy, thereby improving the comprehensiveness of the biopsy and the accuracy of diagnosis. Especially in complex or diseased areas, more tissue information can be obtained; and magnetic drive multi-needle biopsy is adopted, which can be remotely controlled without an internal power supply, realizing multi-directional precise sampling, laying a foundation for the precise sampling technology of digestive tract diseases in the clinical process.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit them. Although the present invention has been described in detail with reference to the foregoing embodiments, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments or perform equivalent replacements for some of the technical features. These modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A magnetic multi-needle biopsy capsule robot, comprising a capsule shell, characterized in that: The capsule shell has end through holes at both ends, a side through hole is formed on one side of the middle of the capsule shell, and the interior of the capsule shell is divided into a left chamber, a middle chamber and a right chamber; The middle chamber is provided with: A first biopsy needle, arranged corresponding to the side perforation; a first permanent magnet, the first biopsy needle being fixed on the first permanent magnet, and the first permanent magnet being configured to drive the first biopsy needle to extend out of the side puncture hole under the driving of an external magnetic field; as well as A resetting mechanism, configured to drive the first biopsy needle to reposition; The left chamber and the right chamber are both provided with: a second biopsy needle disposed corresponding to the adjacent end perforation; A second permanent magnet, wherein the second biopsy needle is coaxially fixed to an end of the second permanent magnet, and the second permanent magnet is configured to drive the second biopsy needle to rotate and extend from the adjacent end perforation under the driving of an external rotating magnetic field; as well as The spiral structure is configured to enable the second permanent magnet to move along its axis when the second permanent magnet rotates around its axis.

2. The magnetic multi-needle biopsy capsule robot according to claim 1, characterized in that: The two magnetic poles of the first permanent magnet are arranged at two ends of its axial direction, and the two magnetic poles of the second permanent magnet are arranged at two sides of its central axis; in an initial state, the magnetic poles on the same side of the first permanent magnet and the second permanent magnet have the same polarity.

3. The magnetic multi-needle biopsy capsule robot according to claim 1, characterized in that: The reset mechanism comprises: Two slide rails are provided and are arranged on both sides of the first permanent magnet, and the slide rails are arranged along the radial direction of the capsule shell; A slider is slidably mounted on the slide rail, and the first permanent magnet is fixedly connected between two of the sliders; A return spring is sleeved on the slide rail and located between the first permanent magnet and the side through hole.

4. The magnetic multi-needle biopsy capsule robot according to claim 1, characterized in that: The spiral structure comprises: A spiral block wrapped around the second permanent magnet; A spiral groove is arranged on the inner circumferential wall of the capsule shell and is adapted to the thread of the spiral block. Both the left chamber and the right chamber are provided with the spiral groove.

5. The magnetic multi-needle biopsy capsule robot according to claim 4, characterized in that: A baffle is fixedly connected to the inner cavity of the left chamber and the right chamber near the adjacent end perforations. The baffle is located on the side of the spiral groove away from the first permanent magnet. A through hole is penetrated on the baffle for the second biopsy needle to pass through.

6. The magnetic multi-needle biopsy capsule robot according to claim 4, characterized in that: The spiral directions of the spiral grooves in the left chamber and the right chamber are the same.

7. The magnetic multi-needle biopsy capsule robot according to claim 1, characterized in that: The first biopsy needle and the second biopsy needle both have an oblique tip, and the inner cavity of the oblique tip has barbs, and the barbs extend toward the direction close to the middle of the capsule shell.

8. The magnetic multi-needle biopsy capsule robot according to claim 1, characterized in that: Two partitions are fixedly connected inside the capsule shell, and the two partitions divide the capsule shell into the left chamber, the middle chamber and the right chamber.

9. A control method for a magnetic multi-needle biopsy capsule robot, based on a magnetic multi-needle biopsy capsule robot as claimed in any one of claims 1 to 8, characterized in that: The following steps are involved: S1. The patient swallows the capsule shell, and the capsule shell is attracted by an external magnetic field to move the capsule shell to the lesion; S2. Based on the consistent polarity of the first permanent magnet and the two second permanent magnets on the same side, the capsule shell is fixed with a first external magnetic field; S3. When the first biopsy needle is needed to take a sample, the first permanent magnet is repelled or attracted by the second external magnetic field, so that the first permanent magnet drives the first biopsy needle to extend from the side perforation, wherein the magnetic field strength of the second external magnetic field is greater than the magnetic field strength of the first external magnetic field; S4. When the second biopsy needle is needed to take a sample, the corresponding second permanent magnet is driven to rotate in the capsule shell by an external rotating magnetic field, and with the help of the spiral structure, the second permanent magnet drives the second biopsy needle thereon to extend out from the corresponding end perforation, wherein the magnetic field strength of the external rotating magnetic field is not less than the magnetic field strength of the first external magnetic field.

10. The control method of the magnetic multi-needle biopsy capsule robot according to claim 9, characterized in that: When controlling the second biopsy needle of the left chamber to take a sample, the first external magnetic field is first moved to correspond to the middle chamber and the right chamber, and then the external rotating magnetic field controls the second permanent magnet in the left chamber; the same is true when controlling the second biopsy needle of the right chamber to take a sample.

Images